Although in the past a number of different types of spray apparatus have been developed, none of such known apparatus has been completely satisfactory for one or more reasons. First of all, it is desirable that such apparatus be capable of efficiently and accurately admixing planting materials such as fertilizers, herbicides, insecticides, fungicides and the like, with a pressurized water stream, and known equipment for doing this has been relatively complex and expensive, and not sufficiently accurate. Moreover, in the past, where an attempt was made to avoid complexity and/or expense, the resulting devices were found to be generally unreliable.
It has also been found desirable for the spray apparatus to be capable of exerting a spray outlet at several different, selectively provided flow rates with prescribed ratios of water to premix materials. Still further, since such equipment is conventionally connected to a water hose and includes a container within which the fertilizer, insecticide, or the like is carried, all of which is hand carried, adjustability of the spray pattern over a wide range is clearly advantageous in providing the optimal spray for particular applications while eliminating the need for holding the apparatus at awkward and tiring angles during use. Again, past systems capable of providing different spray flow and proportions in a variety of dispensing patterns were expensive and complicated to manufacture, or, where designed with an eye toward reducing expense, suffered a significant drop in reliability. Also, the accuracy of proportioning premix materials with water is of critical importance with many materials, and previous known devices for doing this have simply not been suitably accurate for many materials.
With the many different kinds of fertilizers, insecticides, herbicides and the like available on the market, it is necessary that the apparatus used be capable of providing a specified ratio of mixing for each material prior to use, and this has either been relatively difficult to accomplish with prior equipment or not possible at all. For example, in certain types of known spray equipment, the material container has to be removed from the spray equipment and mixing performed within the open container, after which it must be reassembled for use. This, of course, takes time and occasionally produces the undesirable result of the user getting the water and materials onto his hands and clothing, which, since the materials are quite frequently toxic, can be dangerous to the user.